Scooter with motors in the wheels?

I bought an electric scooter that has 2 motors one in the front wheel and one in the back wheel for some reason the back motor only works when it wants too. I have no idea what to do or the make or modle of this scooter. Any help would be gratefully appreciated.

I would consider myself fortunate it's not running all the time, otherwise the battery drain would be enormous. It may well be by design, also.. When running on level ground the amount of torque needed to maintain speed is very little indeed, so it would be very inefficient to have both motors going. Even if both are running you're not going to have an increase in speed.. Does it kick in when going up hills? That is where two motors can help a lot.. In fact i was seriously considering adding a second to my scooter (as I live in a hilly area), but the wiring knowledge needed would be over my head..
HTH